Bolt and nut lock.



No. "if/93,3241.

Sterne Itatenteci (fuiy d, tititi.,

artnr trice..

lJHN V. UULLINEY, UF LEBANON, lltNNEtYLVftNt/t, ASIGNOR T AMERUAN QiRON ANI) STEEL itiAN UFA'lUltlNG CO., INU., UF

LEBANN, PENNSYLVANIA.

lEtltff MND Ntlmlf ttfiltmtt.

SPECIFIGAJON forming part of Letters Patent No. 793,824, dated July d, limiti.

Application tiled December 15,1904, Serial No. 236,926.

le it known that i, JonN V. CULLi'NmY, a citizen of the United States, residingl in Lebanon, county of Lebanon, State of Pennsyl- Vania, have invented certain new and useful improvements in l-Solt and Nut Locks, of which the following is a specification.

My invention relates to that class of bolts and nuts :in which the threads are so proportioned relatively as to cause the screws to jam or lock in forcibly engaging them, so to prevent iuiintentional relative movement, and more particularly to that type in which the threads of the complementary screws are of li ke pitch, but of different shape in cross-section.

ll/lfy invention consists in providing one of the engaging' screws, preferably the nut, with an abnormallyshaped thread adapted to be practically conformed to the normally-shaped thread of the other screw when Yforcibly en- `raged with the latter, the abnormally-shapcd thread beingof greater width than the intervening groove, but having;l yielding' sides adapted to be forcibly closed together by the engaging' thread, so that both the threads and the grooves of the engaging partel will be practically conformed, the parts, however, being firmly retained in adjusted relative position by the resulting' friction and the resilience of the pressed-tog'ether sides of the thread.

Tlhe invention is lfrdly described in connection with the accom panying drawings and is specifically pointed out in the claims.

lfig'nre l shows in central loiigitudinal scction a l)artially-engaged boltand nut embodying` my inventiol'i, thel disengaged portions showing;` the originati shape of the resiiiective threads and the engaged portions indicating,l the change of shape reirniltingl from forcing the nut upon the bolt. VFig. 2 is a separate view of the nut, certain of thc divided threads beingl indicated as closed together partially or wholl y in the process of manufacture to facilitate starting,` the nut upon a bolt. lfig'. 3 shows a portion of a thread-cutting` tool adapted for tapping' the nut .shown in Figs. l and lfig. Li shows a moditication in which the divided thread formed upon the bolt and an ordinary thread in the nut, the dividingg'roove beingI shown of the same eine and chape aa the ,groove between the threads.

As shown in ifig'. i, the bolt is provided with a tf-thread of United States standard Shape thrtnighout, the pitch, however, being` exaggerated for clearness of illustration, while the nut is provided with a double or divided thread of the same pitch and same height as the bolt-thread and the separated parts of which have approximately the same total area of cross-section as the single solid thread of the bol t and are capable of being,l forcibly bent or de'iiected toward each other, so as to form jointly an approximately solid thread of substantially the same shape and size as the bolt-thread and as the intervening' ,groove of the nut when enlarged by the Vforcible engagement of the latter, as indicated.

Vthe dividing-groove (rf, which separates the two parts of the nut-thread show n in Figs. 1Y and 2, is smaller than the main groove@ between the convolutions of the divided thread, so that the separated parts /2 7) may be preseed together with as little expenditure of power as ie required to insure the proper' gripping' ofthe bolt and nut threads. The combined cross-sectional areas of the dividiuggroove u/ and of the main groove t is approximately eenai to that of the `e'roove A of the boltthread, and the total cross-sectional area of the divided thread, including' the two similar parts 7) is approximately equal to that of the thread .i of the bolt, and when said parts b are pressed together in forcingI the nut upon the bolt they jointly lform a snbstam tially solid thread similar to the bolt-threanl B and snugly crowded inte the bolt.-p,'i'ori ve it, while the main ,ermive f/ is at the same time forcibiy enlarged, so as to conform with the bolt-thread li, so that when the nut is `fully engaged with the bolt the 11lit-tli1' iad and groove are both forcibly conformed to the boltthread and groove or, in other werds, are forced into normal shape, so that both the bolt and nut threads will appear in central longitudinal section the saine as an ordinary bolt and nut. YIt is obvious, however, that in natural resilience ot' the metal in the originally-separated thread parts will constantly tend to spread said parts such gripping action will not only be insured while the parts i are retained in engagement, but will also peri mit the forcible removal of the nut and its subsequent rengagement with the bolt without losing the gripping action, though such action may be reduced by thus repeatedly applying the nut.

vWhile I generally prefer to provide the nutscrew with my divided thread, it is evident that the same result may be obtained byproviding it on the bolt instead and using in connection therewith a nut with the ordinary solid thread, as indicated in Fig. A, and while it is preferable that the dividing-groove hetween the thread parts should be reduced so as not to unnecessarily spread said parts, and thereby-require the application ot' undue force to bend or deliect them so as to occupy the space provided by said groove, yet the shape and size ot the latter (and ot' the thread parts correspondingly) may obviously be varied so long as they provide for pressing the separated parts together as described. Thus in Fig. t a double thread is provided on the bolt, the parts of which are separated by a dividing-groove et' the same shape and size as the main groove, thereby forming a very wide divided thread and necessitating' a considerable deflection ot` said parts in forcing the solid-threaded nut thereon, as shown', but as the parts oi' the divided thread are ot' the same height as the solid thread of the nut and not more than halt' the width or thickness of the solid engaging thread such deiection is readily effected, as l have-found in actual practice with V-threads otl United States standard proportions.

In Fig. 3 is shown a portion of a cutting'- tool adapted for tapping the divided threadnut of Figs. l and 2, said tool being' provided with thread-dividing teeth 13, differing in form or size from and located intermediate of the cutting-teeth ai for the main groove, and the combined areas or' one of said dividing-teeth and one ot' said main teeth being equal to or slightly less than the divided tooth-forming grooves 7/ 712. After tapping the nut with this tool in the ordinary manner I in some cases follow it with an additional operation to effect a preliminary closing together of certain of the divided threads, as indicated in Fig. 2, for the purpose et facilitating the starting of the nut upon the bolt by the thumb and linger, such operation consisting merely in forcingthe nut to a limited distance upon a closing-tool which is threaded to correspond with the bolt upon which the i' nut is intended to be used. The divided thread may ot' course be termed upon the bolt instead of the nut, it' desired, in a similar manner.

lt will be seen that my invention provides for the employment ot' either a male or female screw of ordinary thread formation in connection with an engaging screw, the thread of which is forcibly closed together in service, so as to conform with said ordinary thread, while providing a positive and resilient gripping action.

rhat l claim is# l. A screw havingadivided thread the parts of which are capable of being pressed together to forni an approximately solid thread.

2. A screw having a thread with yielding sides of normally greater spread than the intervening groove.

3. A- screw having' a thread with yielding sides ot' normally greater spread than the intervening groove and equally inclined to the aXis around which the screw is formed.

A screw having adivided thread the parts of which are normally spread to form a wider thread than the groove between the threads.

5. A screw having a thread with yielding sides otl normally greater spread than the intervening groove but capable of being pressed together so that the thread and groove will be substantially alike.

6. A screw having a thread the side walls of which are capable of being resiliently pressed together.

7. Ascrewhavingalaterally-closablethread of normally greater width than the intervening groove.

8. Ascrew having a double thread the parts of which are capable of being pressed together to form a single thread.

9. A bolt and nut both of which are screwthreaded to the same pitch, one with a single thread, and the other with a divided thread the separated parts of which are pressed together in Yforcing the nut upon the bolt.

10. Aboltand nut both of which are screi threaded to the same pitch, one with a single thread, and the other with a divided thread the separated parts ot' which are pressed together in forcing the nut upon the bolt to form an approximately solid thread.

l1. A bolt and nut both of which are screwthreaded to the same pitch, one with a single thread, and the other with a divided thread the separated parts ot' which are resiliently pressed together in forcing the nut upon the bolt.

l2. A bolt and nut both of which are screwthreaded to the same pitch and one of which has its threadformed with yielding sides ot' normally greater spread than the intervening' groove.

13. A bolt and nut both ot' which are screwthreaded to the same pitch, one with a single thread, and the other with a divided thread the parts of which are normally spread to IIS reaeea Form a wider thread than the groove between. the threads.

14. A holt and nut both of which are serewthreaded to the same piteh, one with a single thread, and the other with a divided thread the parts of which are normally spread to forni a wider thread than the groove between the threads said parts being' pressed tog-ether in forcing' the nut upon the holt so as to make the thread and groove substantially alike.

15. A holt and nut both of which are serewthreaded to the saine piteh and one o1l which has its thread formed with yielding sides of normally greater spread than the intervening groove and equal ineline to the screw-axis.

16. A bolt and nut both oi' which are screwthreaded to the saine piteh, one with a single thread, and the other with a divided thread the parts of which are equally inclined to the screw axis and normally spread to forni a wider thread than the groove between the threads.

17. A holt and nut both oli' which are sere7W threaded to the saine pitch, one with a single thread and the other with a double thread, the combined cross-seetional areas ol' the two parts oi the double thread being substantially the saine as that of the single thread and said parts heine pressed together in forcing the nut upon the bolt.

18. A screw havinfgl` a divided thread the parts of which are Separated by a groove of less size than the groove between the threadsn 19. A sei-ew having a divided thread the parte oi' which are separated by a V-,g'roove of more acute angle than the V-groove between the threads.

1n testimony whereoll aiiix my signature in the presence of two witnesses.

JHN V. CULLlNEY.

Witnesses:

DAVID M. Fin?, W. H. CAs'rNnn. 

